Opening and closing device for vehicle doors



Nov. 4, 1958 E. G. SKOGSBERG ET AL 2,359,034

OPENING AND CLOSING DEVICE FOR VEHICLE DOORS INVENTORS .5567;

fiC/iarnel znwz 65,5220

Fa/r5 Filed Jan. 19, 1956 v i 2 6/ A51 [7/5 A! ATTORNEY5 United StatesPatent OPENING AND CLOSING DEVICE FOR VEHICLE DOORS Ernst GeorgSkogsberg and Karl Henning Harnell, Ornskoldsvik, Sweden, assignors toAktiebolaget Hiigglund 6r So'ner, Omskoldsvik, Sweden This inventionrelates to a mechanism for automatically opening and closing the doorsof vehicles, and particularly the exit doors of busses operated by onlyone person. The use of such singly operated vehicles has become more andmore usual, and to reduce the drivers work and prevent clamping ofpassengers in the doors, the vehicles have been equipped withautomatically opening and closing doors. This effect has been obtainedby means of two different systems. 7

One of these systems functions as follows: At the halting-place, thedriver tightens the brakes and feeds current to contacts, which arecontrolled by step plates or treadles. These contacts conduct thecurrent to the door operating means. When a passenger steps down on saidstep plates or treadles, which are placed in the steps, the door opens,and when he leaves the treadle, the door closes.

The other system works substantially on the same principle, only thetreadles are replaced by light beams directed past the door opening. Thelight beams actuate a photoelectric cell, which in turn controls thedoor operating means. When a passenger breaks the light beam, the dooropens, and when the light beam falls on the photoelectric cell again,the door closes.

However, the above systems involve the drawback that a certain time willlapse after the driver has brought the vehicle to a stop and before thedoor is being opened by a passenger stepping on the treadle, or breakingthe light beam, respectively. This loss of time will increase if thepassenger first to leave is not accustomed to the system and hesitatesto walk towards a closed door or is afraid of being clamped in it.

This invention has for its object to eliminate the drawbacks of theprior systems and is chiefly characterized by the brake system of thevehicle being combined with a control means, which is adapted to openthe door automatically independently of any other operating means afterthe vehicle has been braked to stop and the brakes tightened at ahalting-place, to hold the door open during a predetermined period, andto close the door automatically after the lapse of this period, providedthat no other means for keeping the door open have entered intofunction. Thus, when the driver has stopped the vehicle at ahalting-place and tightened the brakes, the door will simultaneouslyopen automatically and remain open for a certain time, during whichpassengers will have time to reach the door and step down on the stepplate or break the light beam respectively. If no passenger has steppedon the step plate or broken the light beam within the predeterminedperiod, the door closes automatically. However, if a passenger steps onthe step plate or breaks the light beam, the door is kept open andcloses again independently of the said predetermined time interval.

Another feature of the invention is that this first opening of the doorsis obtained only if some passenger has signalled to the driver that hewants to leave the vehicle at the next halting place. This arrangementserves the purpose of preventing passengers waiting at a. haltingplacefrom entering the vehicle through the exit door, which they could do incase the door opens without any passengers stepping out.

Vehicles such as busses and tramcars are always pro vided with a signaldevice, through which the passenger can signal to the driver that hewants to leave at the next halting-place. Usually, this device consistsof contacts, such as push buttons, mounted in several places in thevehicle, or a signal cable. running along the sides of the vehicle andin turn actuating a contact. The contact actuates a relay, whichconnects the current to a signal lamp placed in front of the driver andalso to the lamps of a sign, which usually is placed in the ceiling andcarries the text Halts. The lamps are lighted until the exit door opens.Then a contact is actuated and the excitation current for the relay isinterrupted.

Further objects and advantages of the invention will be more apparentfrom the following description taken in connection with the accompanyingdrawing which is a circuit diagram illustrating a preferred embodimentof an opening and closing mechanism for vehicle doors.

Referring to the drawing the numerals 26 to 30 indicate a control relayfor a double magnet valve 31, 32, B for locking the vehicle brakes bymeans of a pressure medium cylinder B, 10 to 13, a control relay for adouble magnet valve 21, 22, D controlling the vehicle door by means of apressure medium cylinder D, and relay 5, 7. Upon energization of coil 5switch arm 6 is attracted away from its contact 6 and the circuitthrough light 8 is interrupted. Numeral 1 indicates an illuminatedsignal plate with the text Halt, 2 a control lamp in front of thedriver, 3, 3', 3 push button contacts actuated by the passengers andplaced within reach at different positions in the vehicle, 4 a contactmeans actuated by the door and which is closed as long as the door isnot quite open. Numeral 8 indicates a lamp which throws light on aphotoelectric cell 9, 14, a retardation mechanism. Numeral 23 designatesa control or signal lamp which is lit as long as the door is open, 24 acontact actuated by the driver when the door is to be opened, 25 acontact mechanically coupled with the start controller of the vehicle,for example the throttle pedal.

The mechanism operates as follows: When a passenger wants to alight fromthe vehicle at the next halting place, he informs the driver byactuating one of the push button contacts 3 to 3 thereby illuminatingthe signal plate 1 and the control lamp 2 connected in paralleltherewith and located near the driver and switching in relay 5, thecontact 7 of which causes relay coil 5 to remain energized even afterthe contact 3 has been released. When the driver puts on the brake nearthe halting-place and actuates contact 24, the control relay coil 26 isenergized. The contact means 28, 29 are closed and the double magnet airvalve 31, 32, B is energized by the coil 31 in such a manner that thebrake coupled with the double magnet 31, 32, B is locked by means of theservomotor B connected with valve B. At the same time as the coil 31 isenergized, coil 10 of the control relay 10 to 13 is fed through thephotoelectric cell 9 this resulting in the contacts 11, 12 of the relay1043 being closed thereby operating the retardation mechanism 14. Thisarrangement, consisting of a piston 15 movable in an air cylinder 15',is coupled with the contact member 12, shown in its normal position. Thepiston 15 is loaded by a pressure spring 16. In front of the piston anoutlet channel 18 with a throttle screw 19 is arranged. At the oppositeside the cylinder is open at 20. The retardation arrangement acts insuch a way that relay Ill to 13 operates immediately and contact members11, 12 are closed. On the other hand the relay 10 to 13 releases at arate predetermined by the adjustment of the retardation mechanism 14.

When the contacts 11, 12 of relay 10 to 13 are closed the coil 21 of thedouble magnet valve D is energized. this magnet valve controlling theair cylinder D for opening the door. When the door has reached its openposition the contact 4 is actuated by the door and relay coil 5 is cutout, thereby causing contact 6 to close and contact 7 to open wherebythe signal plate 1 and the control lamp 2 are extinguished. Upon theclosing of switch arm 6 against its contact 6 the lamp 8 is fed, thislamp being placed at one side of the door and lighting the photoelectriccell 9 at the other side of the door. Thus, lamp 8 is extinguished theresistance of cell 9 increases considerably and relay coil 10 loosescurrent so that contact member 12 moves to contact member 13 at aretarded speed defined by the piston arrangement 15. After the contactmembers 12, 13 have been closed the coil 22 of double magnet valve D isfed, this magnet valve actuating the door operating cylinder D to closethe door.

The device described as before acts in such a manner that the door isopened immediately when the brake has been locked by means of the doublemagnet valve B and is closed after a fixed time predetermined by theretardation arrangement provided that no passenger breaks the beam oflight from lamp 8 to photoelectric cell 9. If a passenger breaks thebeam the control relay coil 10 will be fed thus holding the door open.The door will be closed first after the beam has been broken and whenthe retardation time has expired.

The brake is released by pushing the throttle pedal, the contact means25 being closed. Thus the coil 27 of control relay 26 to 30 is fed, thecontact members 29, 30 are 0 closed and the double magnet valve B isenergized in such a way that the brake is opened.

The auxiliary means shown in the drawing, for instance, the relays, caneven be replaced by other suitable means with the same functions. By wayof example the double magnet valves B, D, with control relays 10, 26, 27can be replaced by stepping relays and likewise the retardationarrangement shown can be substituted by other mechanically operatedmeans or even by electronic devices. Instead of the photoelectric cellshown in the drawing movable step plates with mechanical contact meanscan be used or the cell can be completed by an electronic relay circuitas to obtain a sufficient feed current for the controlling relay 10 to13.

The arrangement should preferably be completed with means which can beregulated by the driver or the service staff to vary the period duringwhich the door is held open.

The above described arrangement is believed to eliminate the drawbacksof the door opening systems hitherto used in singly operated vehicles,among other things by reducing the halting time.

Obviously the details of the above arrangement can be modified inseveral ways without departing from the spirit of the invention.

We claim:

1. A control system for road and rail passengervehicles, which vehicleshave a door and vehicle brakes arranged for operation by servo-motors,air valves for controlling said motors, respectively, electromagneticmeans for controlling said air valves, respectively, a brake circuitincluding said brake controlling electromagnetic means, switch means insaid circuit in position to be operated by the vehicle operator, a dooroperating circuit including said door operating electromagnetic means, aswitch in said door operating circuit located in position to be operatedby the vehicle operator, said door operating circuit including a secondswitch having a movable part, a retardation mechanism connected to saidmovable part and having means pressing said part in one direction andhaving means retarding its speed of movement, electromagnetic meansattracting said movable switch part in one direction against thepressure of said pressing means when fed with suflicient current, a doorcontrolling circuit including said electromagnetic switch partattracting means, a photoelectric cell connected in said doorcontrolling circuit, an electric light source also connected in saiddoor controlling circuit and located in position to effect theresistance of said photoelectric cell, a signalling circuit including apassengers signal switch for closing said signalling circuit, saidcircuit including a signalling device for apprising the operator apassenger desires to leave the vehicle, a relay coil in said signallingcircuit, a movable switch arm under the control of said coil formaintaining said signalling circuit closed after release of saidpassengers signalling switch, a second switch located in position to beoperated by said signalling circuit relay coil to be opened when saidrelay coil is energized, said second switch being connected in thecircuit of said light source to extinguish said light source when saidsignalling circuit relay coil is energized, said second switch, whensaid relay is not energized, being closed and the light sourceilluminated to increase the resistance of the said photoelectric celland prevent energizing of said door-operating electromagnetic meanswhereby the door does not open, said second switch, when said relay isenergized, being opened to extinguish said light source, therebydecreasing the resistance of the photoelectric cell and energizing thedoor-operating electromagnetic means and moving the second switch in thedoor-operating circuit into position for opening the door, a thirdswitch in the signalling circuit, means connected with said door foropening said third switch when the door is opened for opening thecircuit to said relay coil whereupon the second switch in the signallingcircuit is closed, and the light source illuminated, thus increasing theresistance of said photoelectric cell and allowing release of saidmovable part of said second switch of said door operating circuit topermit said retardation mechanism to press and move said movable part insaid one direction for effecting completion of the circuit to said doorclosing electro-magnetic pneumatic valve control means.

2. A control system for road and rail passenger vchicles, which vehicleshave a door and vehicle brakes arranged for operation by servo-motors,as claimed in claim 1, and in which said electric source of: light andsaid photoelectric cell are located on opposite sides of the vehicledoor so that the light from said source to said cell is obstructed by apassenger leaving through the door.

Parvin Mar. 17, 1936 Johnson et al. Oct. 19, 1937

